This process has already produced helpful findings. “Energy is the biggest lever at our disposal because our processes and production operations have such high demands.” What he is referring to here are clean rooms, the spaces in which ZEISS manufactures the lenses and mirrors for lithography optics. The requirements for air purity are very strict. “Our energy consumption is high because we need heavily air-conditioned clean rooms. Nonetheless, we are constantly optimizing our infrastructure.” For example, consumed energy is reused smartly and process waste heat is reclaimed in heating systems. “Microchips are used for this as well,” says Ingo Hofmann,
“They are a basis for intelligent switches that we can use to optimize our production halls.” His team questions everything: Does the machinery need to be in the clean room, or would a less energy-consuming area suffice too? The latter can reduce the area needed for clean rooms, which in turn has a positive influence on energy consumption. This is something that ZEISS looks at closely when moving into newly constructed buildings. It is also just as important that employee awareness is raised. “Which processes can we improve? How can we stop machines from being on standby for an unnecessarily long time? The ZEISS mindset is known to be about efficiency and precision, and our aim is to refine this mindset in relation to sustainability, too,” says Ingo Hofmann. There are also initiatives that can be taken for resource consumption. “We are currently looking at using ‘green steel.’ Manufacturing steel consumes a great amount of electricity, so it is usually associated with significant carbon emissions. If the electricity used for it is generated from renewable sources, this process can be completed in a considerably more sustainable way,” says Tobias Berndt. However, on a critical note, he adds, “There is always a question you need to ask: How was this electricity made ‘green’? Through carbon offset certificates – which generally are OK – or by actually using renewable energies with power purchase agreements (PPAs)? The latter is even better because in that case there is never even any carbon dioxide produced that you would have to offset later on. This is something we are investigating right now.”